7.5
**Analyse** and **present information** from secondary sources to trace the history of the selective breeding of one species for agricultural purposes and use available evidence to **describe** the series of changes that have occurred in the species as a result of this selective breeding

History of Selective Breeding for Wheat:
- Growing of wheat started 10 000 years ago in ancient Mesopotamia - Growing of wheat grew to Europe, Asia, North Africa and China before 1000 BC - Wheat was grown in Australia in 1788 but would not grow efficiently due to soil and amount of rainfall and the new diseases that were in the country e.g. stem rust - William Farrer obtained many different types of wheat in 1882 - He bred many different types together and produced many hybrid varieties - He worked out through trial and error which were inherited through the wheat as he did not know about Mendel’s laws - 1902 – ‘Federation’ was released which matured early, had a high yielded and fairly high resistant to rust and could be grown in drier areas which was beneficial as this meant a smaller chance of fungus growing- Soon, over 80% of the population of wheat in Australia was the strain - ‘Federation’ - He also began to breed strains that were resistant to their diseases - By 1912, Wheat became Australia’s most important crop
Series of Changes that have occurred in the species through selective breeding: - Through artificial pollination (breaking the stamens off a flower and dusting the pollen onto the stigma of the same flower or a different flower) we are able to have a great degree of control on breeding and the results of this - These results were greatly increased through Mendel’s findings in 1900- During the 20th century, people were able to make thousands of new breeds- In the 1940s, a team led by Norman Borlaug spent 20 years breeding high-yield dwarf wheat which produced a higher yield and was he most pest resistant variation seen- Because of this, nearly 80% of the world’s wheat is from Borlaug’s work which was known as the Green Revolution- This involved producing thousands of variations of wheat such as shorter plants, smaller root systems and even smaller leaves- This has been especially helpful in countries such as Australia with soils and conditions that make it hard to grow these plantsexternal image wheat.jpgexternal image wheat.bmp
Developing and planting wheat varieties that resist diseases and insects is essential for a secure food supply, human health, and reducing the use of chemical controls. For example, fungal diseases like Karnal bunt, leaf rust, or smut will ruin entire wheat crops

Through centuries of seed selection and modern wheat breeding, wheat can be grown in every temperate climate in the world. World wheat production is perennial, that is, wheat is being harvested in some part of the world in every month of the year.